The HAPTIX program will develop new science and technology to achieve closed-loop control of dexterous mechatronic prostheses that will provide amputees with prosthetic limb systems that feel and function like natural limbs. HAPTIX will focus on development of implantable peripheral interfaces for volitional motor recording and sensory feedback signals; implantable electronic systems to transferport information between these interface(s) and the prosthesis; and sophisticated encoding and decoding algorithms to transform recorded volitional motor control signals into limb movements and patterned stimulation into naturalistic touch and proprioceptive sensations. System performance and the ultimate benefit to prosthetic users will be determined in a year-long, take-home trial before the end of the HAPTIX program.